Drugs in powder form are generally distributed in vial bottles in which the drugs are sealed in a gas-tight manner. To administer such a drug to a patient, a solvent is injected into the vial bottle, the drug is dissolved in the solvent to obtain a drug solution, and then the drug solution is transferred from the vial bottle into a drug solution bag. After that, the drug solution within the drug solution bag is administered to the patient. The injection of the solvent into the vial bottle and the extraction of the drug solution from the vial bottle are performed by piercing a stopper (rubber stopper) that seals a mouth (opening) of the vial bottle with a piercing needle (sometimes referred to as “bottle needle”).
There are cases where the drug contained in the vial bottle is a drug that is designated as a powerful drug like an anticancer agent, for example. Adhesion of such hazardous drugs and their drug solutions to the finger or the like of an operator and inhalation of such drugs and their vapor by the operator must be avoided. Thus, a connector is known which enables a series of operations from the transfer of the solvent within the drug solution bag into the vial bottle to the transfer of the drug solution within the vial bottle into the drug solution bag to be performed while the connector remains connected to the vial bottle and the drug solution bag (see Patent Documents 1 and 2, for example). This connector does not need to be repeatedly connected to and disconnected from the vial bottle and the drug solution bag in the process by which the prepared drug solution is obtained within drug solution bag. Therefore, the possibility that the drugs and the drug solutions may escape to the outside environment is generally low.